1. Field of the Invention
The present invention relates to a camera and more particularly to a camera in which information such as photographing information can be recorded on a film as magnetic data or the camera using a film cartridge which accommodates a film in a light-intercepted condition.
2. Description of the Related Arts
U.S. Pat. No. 4,482,924 and Japanese Patent Laid-Open Application No. 60-17447 disclose a film having a magnetic material applied to the back surface thereof so that data such as photographing information and the trimming information of a pseudo focal length photographing can be magnetically recorded during a photographing operation. A camera using this kind of film contains a magnetic head for recording data on the magnetic surface formed on the film and a pad for sandwiching the film between the magnetic head and the pad.
In initial film loading of the camera, the leading end portion of the film strip is wound by the spool provided in the camera. In a camera in which magnetic data is recorded on the magnetic surface of the film, it is necessary to pass the film between the magnetic head and the pad. Particularly in a camera in which the film is automatically loaded, in order to reliably pass the film strip between the magnetic head and the pad, it is preferable to move the magnetic head and the pad away from the film feeding path and keep them in contact with the film when magnetic data is written onto the magnetic surface of the film or data recorded thereon is read. In order to keep the film surface properly oriented during a shutter release operation, it is also preferable that neither the magnetic head nor the pad is in contact with the film. In order to prevent the magnetic material on the film surface from being transferred to the magnetic head, preferably, the magnetic head should be spaced from the film except when data is written onto the magnetic surface of the film or data recorded thereon is read.
It is necessary to provide the camera with a mechanism for effectively moving the magnetic head and the pad with respect to the film feeding path. Preferably, the mechanism is constructed in consideration of the miniaturization of the camera and cost reduction.
In a camera into which the film is automatically loaded, it is unnecessary to pull out the leading end portion of the film strip from a film patrone or a film cartridge. That is, after the patrone or the cartridge is inserted into the camera body, the film is automatically loaded. In a camera in which the patrone or the cartridge is inserted into the camera body or taken out therefrom along the axis of the spool of the patrone or the cartridge, mostly, the cover of the cartridge chamber is positioned on the bottom surface of the camera body. In taking out the cartridge from the cartridge chamber, the cover is opened with the camera body inverted and then, the camera is turned again so that the cartridge slips out of the cartridge chamber.
In a more complex camera, the cartridge chamber includes a mechanism for ejecting the cartridge. The mechanism projects the bottom portion of the cartridge from the cartridge chamber when the cover is opened with the camera body turned upside down.
The camera containing the ejecting mechanism is large-sized and its cost of production is high. Additionally the ejecting mechanism causes a user to take out the cartridge inconveniently from the cartridge chamber.
Since the cover is positioned on the bottom portion of the camera body, unless the cover of the cartridge chamber is opened with the camera turned upside down, the cartridge drops from the cartridge chamber as soon as the cover is opened. Accordingly, it is preferable to provide a mechanism in which the cover cannot be opened unless the camera body is turned upside down.